Second Progress Report Covering Period 1 December 1973 to 14 January 1974

Abstract : The work includes results of the hydrophone modeling effort which define the tradeoffs in bender hydrophone design between sensitivity, output impedance, bandwidth, size and depth capability. The design curves also provide guidance on selection of the proper value of ceramic-to-metal thickness ratio to achieve a given set of performance parameters. Some preliminary results in the extension of mathematical modeling of hydroacoustic devices is described. A differential equation is developed for a fast moving variable orifice (valve) and expressions are developed for pressure drop and power loss in fixed orifice-like constrictions which pass both steady and acoustic flows.